1. Field of the Invention
The present invention relates to a filter having a changeable filter element, which can be used, for example, for filtering a lubrication oil in an engine.
2. Description of Related Art
Conventionally, a method for changing a filter element disposed in a filter is described in JP-A-8-57209 and U.S. Pat. No. 4,906,365. In the conventional method, before changing the filter element, oil staying in the filter is discharged. However, the filter has a special oil passage for draining the oil into a crankcase of the engine. Therefore, it is difficult to change a filter element in a conventional filter where the special oil passage is not provided.